# Author:Foru

# # 计算频度计数
# vowels = ['a','e','i','o','u']
# word = input("Provide a word to search for vowels: ")
#
# found = {} # 创建空字典
#
# ## 初始频度数
# found['a'] = 0
# found['e'] = 0
# found['i'] = 0
# found['o'] = 0
# found['u'] = 0
#
# for letter in word:
#     if letter in vowels:
#         found[letter] += 1
#
# for k,v in sorted(found.items()):
#     print(k,'was found',v,'time(s).')


# # 无设置初始频度数，可能会导致运行时错误而崩溃
# vowels = ['a','e','i','o','u']
# word = input("Provide a word to search for vowels: ")
#
# found = {}
#
# for letter in word:
#     if letter in vowels:
#         found[letter] += 1
#
# for k,v in sorted(found.items()):
#     print(k,'was found',v,'time(s).')


# # 利用 “setdefault” 方法修正上面那个运行错误（如果没有为一个键设置值，会为它赋值一个默认值）
# vowels = ['a','e','i','o','u']
# word = input("Provide a word to search for vowels: ")
#
# found = {}
#
# for letter in word:
#     if letter in vowels:
#         found.setdefault(letter, 0)
#         found[letter] += 1
#
# for k, v in sorted(found.items()):
#     print(k, 'was found', v, 'time(s).')


# 利用集合数据结构简化
vowels = set('aeiou')
word = input("Provide a word to search for vowels: ")
found = vowels.intersection(set(word))
for vowel in found:
    print(vowel)